Device for moving sliding doors

Abstract: A device for moving sliding doors which includes a mechanism for moving and supporting a door (8) is driven by a DC electric motor (17) and is provided with an emergency operation system in case of black-out consisting of at least one capacitor capable of delivering a capacitive discharge suitable to allow at least two operating cycles of the device. The movement of door (8) preferably takes place along an arc of circumference centered on the vertical, and the device thus includes a spring (12) suitable to make resistance during the lowering of door (8) and to help the rotation during the rising of door (8), whereby the power required along the whole said arc is kept practically constant.

Description: The present invention concerns devices for moving sliding elements and in particular a device for moving sliding doors such as those used to close passageways in areas where control of the people's passage is required (underground stations, factories, offices, etc.). It is known that present moving devices substantially include an AC electric motor which, through a reducer. drives a mechanism which supports the door and makes it slide orthogonally to the direction of passage so as to open or close the passageway. The device operation logic varies according to the specific application, ranging from the passageway always closed and opened only upon clearance (underground) to the passageway always open and closed only upon detection of an error condition (for example connected to a metal detector). Whichever the specific application may be, the use of an AC motor has a serious drawback in case of lack of tension or black-out. In this instance, in fact, the device is no more supplied and can not operate unless it is connected to a no-break power unit, as disclosed, for instance, in FR-A-2619153. Such a unit obviously involves a significant cost and room, and is thus seldom used. Therefore, the devices of the prior art, in general, include just a counterweight which is raised upon closing the doors. so as to give it a sufficient potential energy to drive the opening mechanism in case of black-out. In the opposite case wherein the counterweight is raised upon opening, then it would obviously operate to close the passageway. Finally, it would be possible to arrange the counterweight so that it carries out an operating cycle regardless of the device position at the moment of the black-out, i.e. opening the passageway if it was closed or closing it if it was open. However, any solution adopted allows only the opening or only the closing of the passageway. and just for a single operating cycle. It is clear that this is a problem in those applications wherein the continuous operation of the device even in case of black-out is essential, or in the case in which a change in the situation requires one or more operating cycles in addition to the first one. Therefore, the object of the present invention is to provide a device which overcomes the above-mentioned drawbacks. This object is achieved by means of a device having the characteristics cited in claim 1. A first apparent advantage of the present device is its capacity of performing more than one operating cycle after a black-out, regardless of the condition in which the device is at the moment of the supply breaking off. Another advantage of this device consists in the possibility of maintaining the supply thereto with a no-break power unit much cheaper and smaller than those required by prior art devices. Moreover, the absence of a counterweight is a further advantage, in that the device size is reduced. These and other advantages and characteristics of the device according to the present invention will be apparent from the following detailed description of a preferred embodiment thereof, reported as a non-limiting example, referring to the annexed drawings wherein: Fig.1 is a front view of the present device; and Fig.2 is a side view of the device of fig. 1. In fig.1, there is shown the mechanism according to the present invention for moving and supporting the door. This mechanism includes an articulated parallelogram formed by vertical bars 1, 1' and upper and lower levers 2 and 3, respectively, as well as a rod 4 driven by a crank 5 and finally a pair of moving arms 6, 6' hinged to the support 7 of door 8. The levers 2, 3 are centrally pivoted on a supporting structure 9, on whose opposite side arms 6, 6' keyed onto the same pins of levers 2, 3 move so as to rotate integrally thereto. The upper lever 3 is substantially shaped as an inverted T, having a projecting bracket 10 at whose end there is mounted a fixing pin 11. Said pin 11 is mounted in a position aligned with the axis of arm 6, and the upper end of a spring 12 is fixed thereto. The lower end of spring 12 is fixed to a similar pin 13, centrally mounted on structure 9 in line with the pins of levers 2 and 3. The length of spring 12 is such as to have it always in tension, and its function will be made clear further on. A plate 14 orthogonal to the mechanism rotation plane is located at the base of structure 9. Said plate 14 carries a buffer 15 and a microswitch 16 which stops the motor, at the upper and lower end of the stroke of crank 5. Referring now also to fig.2, there is seen motor 17, which has been omitted in fig. 1 for the sake of clarity, so that the mechanism behind could be completely visible. Said motor 17 is of the DC type and it includes also a reducer and at least one capacitor. In the absence of the network supply, the presence of one or more capacitors allows for carrying out two or more operating cycles, according to the needs, by using the capacitive discharge of said capacitors, which are kept at the maximum charge during the normal operation of the device. The discharge is controlled and regulated by means of a microprocessor (not shown) which provides to the device control both in normal conditions and in case of black-out. It should be noted that the small size of the device in the direction orthogonal to the plane of door 8 is achieved not only by eliminating the counterweight, but also by placing motor 17 with its longitudinal axis in a vertical position. The outlet shaft of motor 17, on which crank 5 is keyed, is vertically aligned with the pins of levers 2 and 3 and with pin 13 along an X axis. This arrangement of the members of the present device is such that the movement of door 8 involves a symmetrical oscillation of levers 2, 3 and arms 6, 6' with respect to the X axis. In the position of fig. 1, crank 5 is at the upper end of the stroke and door 8 is extended to close the passageway. When door 8 must be retracted to open the passageway, motor 17 rotates crank 5 and the whole articulated parallelogram therewith, through rod 4, in the anti-clockwise direction. At the beginning of its motion, door 8 drops and therefore its weight works in favour of the rotation, while spring 12 must be extended and therefore makes resistance to the rotation. At the moment when arms 6, 6' are aligned with the X axis the weight of door 8 stops working in favour of the rotation and on the contrary starts making resistance, while the opposite takes place for spring 12 which starts contracting. In this way, the double result is achieved of having a power need which is practically constant along the whole arc of rotation and the same either for opening or closing the passageway. It is thus possible to optimize the operation of motor 17, which being of the DC type operates better when no power peaks are required. Furthermore, the same power required for opening and closing allows for an optimum sizing thereof, differently from the prior art devices wherein the movement for closing the passageway usually requires a greater power. It is clear that in the case in which the present device is connected to a no-break power unit, the latter can essentially consist in one or more batteries instead of a more complicated and expensive generator required by AC motors of known devices. Obviously, in this case it will also be possible to avoid the use of the capacitors. Clearly, the above-described and illustrated embodiment is just an example, susceptible of various changes. In particular, the mechanism for moving and supporting door 8 may be replaced by any equivalent of the illustrated mechanism, as long as it is driven by the above-illustrated motor 17. Similarly, spring 12 may be replaced by any elastic member suitable for the purpose.

Claims: A device for moving sliding doors which includes a mechanism for moving and supporting a door (8), said mechanism being driven by an electric motor (17) and being provided with an emergency operation system in case of a black-out, characterized in that said electric motor (17) is of the direct current type and said emergency system consists of at least one capacitor capable of delivering a capacitive discharge suitable to allow at least two operating cycles of the device. A device according to claim 1, characterized in that the movement of door (8) takes place along an arc of circumference centered on the vertical, and the device includes a spring (12) suitable to make resistance during the lowering of door (8) and to help the rotation during the rising of door (8), whereby the power required along the whole said arc is practically constant. A device according to claim 1 or 2, characterized in that motor (17) is put in a vertical position. A device according to one of the preceding claims, characterized in that the capacitor and a reducer are integrated into motor (17).

Inventors: BONETTO MAURO, BONETTO, MAURO
Applicants: ITALDIS IND SPA, ITALDIS INDUSTRIA S.P.A.
Application year: 1994
Main classification: E05F15
IPC codes: E05F15